Field of the Invention
The present invention relates to information processing apparatuses, generating methods, medical diagnosis support apparatuses, and medical diagnosis support methods.
Description of the Related Art
In the field of medicine, an image-based diagnosis is performed by a doctor reading a medical image obtained using an imaging device such as an X-ray CT device, an MRI device, or the like and making a diagnosis of a condition based on the medical image. In an image-based diagnosis, an attending physician makes a request to interpret an image, and in response to the request, a doctor makes an overall judgment based on findings obtained from the image (called “image findings” hereinafter) and from various types of measured values and so on, and identifies symptoms of pathologic changes present in the image. Using the image findings, the measured values and so on, the doctor then consolidates the process leading to the diagnosis into an interpretation report for the attending physician who made the request.
Diagnosis support apparatuses for supporting such image-based diagnoses are being developed. For example, Japanese Patent Laid-Open No. 2010-200840 discloses a technique for obtaining an inference result using an inference means based on information that has been input (called “input information” hereinafter) and presenting negative information and positive information as support information in response to the obtained inference result. This makes it possible to present the inference result, as well as information that helped lead to the inference result based on the input information. Here, the inference means is also called as a inference model, which includes data structure for conducting inference, for example a mathematical expression implemented as a software data. An inference model is used to conduct inference to output an inference result based on the input data. For example a CPU (a central processing unit) conducts inference using the inference model to process the input data to output the inference result.
The inference means used in such an apparatus is often constructed using a machine-based learning technique. In this case, the inference means is constructed using training data (called “training data” hereinafter). A general method for constructing the inference means comprises constructing a plurality of inference means and selecting the optimal inference means using an index, such as an information amount reference, for evaluating the performance of the inference means. Meanwhile, although the training data is used under the assumption that the training data is the same as data used during operation (the latter being called “additional data”), there are cases where the training data increasingly diverges from the additional data as operations progress. Accordingly, attempts are being made to reconstruct and update the inference means using the additional data in order to suppress such divergence from the additional data. For example, Japanese Patent Laid-Open No. 2010-262625 discloses a technique that uses estimated values obtained from the additional data and applies the inference means in a progressive manner.
Japanese Patent Laid-Open No. 2010-200840 discloses a technique that uses an already-constructed inference means, and does not disclose how the inference means has been constructed. In light of the purpose of the inference means, it is desirable to present information of validity as the information that helped lead to the inference result. Furthermore, it is desirable to periodically update the inference means in order to prevent divergence from the additional data during operation.
However, typical methods for constructing the inference means focus only on the performance of the inference means, and have not considered how the most valid information can be presented. In addition, there is generally thought to be a tradeoff between the performance of the inference means and the capability to display the most valid information, and so it has been difficult to construct an inference means that meets both needs when focusing only on the performance of the inference means.
Although an inference means that periodically restores the performance of the inference means can be constructed in the case where the technique of Japanese Patent Laid-Open No. 2010-262625 is integrated as well, it is difficult to periodically construct an inference means that also takes the validity of the information presented into consideration.
In light of the aforementioned problems, it is an object of the present invention to provide a medical diagnosis support technique capable of constructing an inference means that takes into consideration both the performance of the inference means and the validity of presented information.